Pneumothorax is a life-threatening condition that occurs when the lung outer membrane is injured by a sharp object and air leaks into the thoracic or chest cavity. The air can then build up inside the chest cavity, compress the heart and lungs and deprive the victim of oxygen. The condition also may cause a drop in blood pressure and, in severe cases, result in sudden death from acute heart failure, Pneumothoraces are observed clinically as a result of many conditions, principally as the result of trauma (i.e. car accidents with rib fractures, stab wounds, and bullet wounds). Pneumothorax can be a complication of central venous catheter (CVC) insertion surgical procedures for intravenous access.
The clinician generally obtains a standard chest radiograph picture when a pneumothorax is suspected clinically. Or, in the case of catheter insertions, X-rays are obtained to prove postoperatively that pneumothorax has not occurred. The radiograph is costly, can be delayed due to personnel or equipment unavailability, and exposes the patient and surrounding healthcare personnel to potentially harmful ionizing radiation. To date, no other method has been described that enables the non-invasive diagnosis or exclusion of pneumothorax without some form of ionizing radiation imaging.
It would be advantageous, therefore, to provide a device to determine if a pneumothorax exists which eliminates the need for chest radiographs in the overwhelming majority of cases. It would also be advantageous if the device can be used to detect heart valve abnormalities, bone and joint problems, and blood vessel flow disturbances.
It is among the several objects of the present invention to provide a device that can detect the presence of pneumothorax without the use of ionizing radiation, or any invasive procedure such as a needle puncture of the skin.
It is another object of the present invention to provide a device that can detect the presence of pneumothorax using ultrasonic techniques.
Another object of the present invention to provide a device that can detect the presence of pneumothorax using passive auditory detection.
Yet another object of the present invention to provide a device that can detect the presence of pneumothorax using mildly radioactive ideal gas.
Yet another object of the present invention to provide a device that can detect the presence of pneumothorax that is portable and easy to use.
In accordance with invention, generally stated, the preferred embodiment includes a passive auditory detection system having an array of listening device (transducers) which can be moved freely over the patient""s body surface. This array returns its signal to the central processing unit which filters, band-shifts and conditions the signal to reject ambient noise and focus on the area of interest. This conditioned signal is then presented to the user auditorily.
In another embodiment, a portable device for detecting a pneumothorax, comprising an ultrasonic probe for coupling the pulse to the chest and receiving the echo. The probe delivers its signal to the central processing unit. The central processing unit performs the correlations, normalizations and then presents the information visually and auditorily to the user.
Another embodiment includes a dispenser/mixer to allow inspiration of a mixture of the mildly radioactive gas and air. The detection device consists of a radiation detecting device such as a scintillation crystal and photomultiplier tube or a Geiger-Mueller tube or a solid-state detector. This detector is coupled to a signal conditioning and presentation system which provides a visual and auditory indication of the received signal strength.
All of three of the embodiments of the device can include an on-board microprocessor or digital signal processor for interpretation of the information, to provide clinically relevant information to the user, and eliminate the need for the user to be able to personally interpret the signals. This interpretation could provide the user with a xe2x80x9cyes/noxe2x80x9d indication of a specific condition, or alternatively, could determine that further testing (i.e., a chest radiograph) was necessary to evaluate for this condition